Abstract 124P
Background
BRAF V600E is identified approximately 5-9% of colorectal cancer (CRC) patients. Non-V600E BRAF mutation is characterized a rare molecular subtype. The clinical characteristics and prognostic impact of non-V600 BRAF mutants are not well defined.
Methods
We recruited 829 patients with CRC from our institution. Tissue samples were molecularly tested. Clinical data was retrospectively reviewed and analyzed using Chi-square and t-test. Overall survival (OS) was compared by log-rank test.
Results
All BRAF mutation was detected in 50 (6%) patients including 24 (3%) patients with non-V600 mutations. Patient characteristics and BRAF testing technique were not significantly different based on BRAF status and it was comparable between BRAF V600E and non-V600 groups. There were significantly more ALL RAS and PIK3CA mutations in non-V600 mutant patients. Patients with non-V600 mutation had median OS of 82 months which was longer than BRAF WT, 66 months, and 31 months of BRAF V600E group, respectively (P=0.067). OS according to treatment with anti-EGFR in metastatic CRC patients was not significantly different in both V600E and non-V600 BRAF mutant groups. Table: 124P
BRAF-MT (n=50) | |||||||
BRAF-WT (n=779) | BRAF-MT (n=50) | p-value | V600 (n=26) | non-V600 (n=24) | p-value | ||
Age | 63 (18 - 93) | 65 (19-85) | 66 (19 - 85) | 65 (24 - 83) | |||
Sex | |||||||
Male | 471 (60) | 32 (64) | 0.62 | 15 (58) | 17 (71) | 0.333 | |
Female | 308 (40) | 18 (36) | 11 (42) | 7 (29) | |||
Sidedness | |||||||
Left | 591 (76) | 33 (66) | 0.289 | 12 (70) | 15 (62) | 0.878 | |
Right | 168 (22) | 15 (30) | 7 (27) | 8 (33) | |||
non-specify | 20 (3) | 2 (4) | 1 (4) | 1 (4) | |||
Technique | |||||||
NGS | 547 (70) | 38 (76) | 0.466 | 18 (69) | 20 (83) | 0.26 | |
Pyrosequencing | 84 (11) | 6 (12) | 5 (19) | 1 (4) | |||
PCR | 148 (19) | 6 (12) | 3 (12) | 2 (12) | |||
All RAS mutation | 418 (54) | 8 (16) | <0.001 | 0 | 8 (33) | 0.001 | |
PIK3CA mutation | 94 (12) | 9 (18) | 0.218 | 1 (4) | 8 (33) | 0.009 | |
Recur/Met | (n=575) | (n=35) | (n=19) | (n=16) | |||
Anti-VEGF | 105 (18) | 7 (20) | 0.796 | 2 (11) | 5 (31) | 0.207 | |
Anti-EGFR | 162 (28) | 6 (17) | 0.156 | 3 (16) | 3 (19) | 1 |
Conclusions
Non-V600 BRAF mutation may indicate better prognosis. The difference in treatment effect was not demonstrated in patients with BRAF mutation.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Faculty of medicine Ramathibodi Hospital.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
26P - Subcutaneous trastuzumab versus intravenous trastuzumab for treatment of patients with HER2-positive breast cancer: A time, motion and cost-benefit assessment in a day care oncology unit in China
Presenter: Bei Sun
Session: Poster Display
Resources:
Abstract
27P - The biological characteristics of HER2-low in TNBC using mRNA profiling and molecular subtypes
Presenter: Asako Tsuruga
Session: Poster Display
Resources:
Abstract
28P - One-week ultra-hypofractionated partial breast RT in early breast cancer: 3DCRT vs IMRT
Presenter: Nurilla Zaynutdinov
Session: Poster Display
Resources:
Abstract
30P - Stereotactic body radiotherapy using cyberknife versus interstitial brachytherapy in accelerated partial breast irradiation on left-sided breast: A comparison of preliminary clinical result and dosimetric characteristics
Presenter: Ting-Na Wei
Session: Poster Display
Resources:
Abstract
31P - Prognostic implication of breast edema on preoperative breast MRI in breast cancer
Presenter: Ki-tae Hwang
Session: Poster Display
Resources:
Abstract
32P - Efficacy of olanzapine in the prophylaxis of delayed chemotherapy-induced nausea and vomiting in breast cancer patients receiving dose-dense AC with a steroid-sparing regimen: A single-center pilot study
Presenter: Manami Tada
Session: Poster Display
Resources:
Abstract
34P - Social support as the mediator of the association between unmet needs and happiness among women with early breast cancer
Presenter: Nithiya Sinarajoo
Session: Poster Display
Resources:
Abstract
35P - Prospective study assessing the efficacy and safety of a scalp cooling device for the prevention of alopecia in breast cancer patients undergoing (neo)adjuvant chemotherapy
Presenter: Winnie Yeo
Session: Poster Display
Resources:
Abstract
37P - To excise or not to excise: Preventive management of early breast cancer in atypical ductal hyperplasia patients
Presenter: Clarisse Hing
Session: Poster Display
Resources:
Abstract
38P - Exploring prognostic factors in patients achieving PCR after neoadjuvant therapy for triple-negative breast cancer: A retrospective study based on SEER data
Presenter: Lv Wenjie
Session: Poster Display
Resources:
Abstract